1. Field of the Invention
The present invention relates to a closure with internal security, for bottles and the like, of the type comprising a body fixable to the mouth of the bottle and defining a fluid passage, a cap for screwing onto the body to close the passage, and at least one valve shutter movable along the passage in the body to engage a valve seat in the passage.
2. Description of Background Art
Closures are known which are particularly intended for bottles of alcoholic liquors and highly-valued spirits which serve to prevent refilling of the bottle so that, once the original valuable contents have been consumed, the bottle cannot be refilled with liquor from a different source, for selling fraudulently as the original.
Although generally satisfying theses requirements, known closures of the specified type currently in use have a functional disadvantage which limits their use.
In particular, this disadvantage lies in the fact that, upon pouring, the desired flow of liquid from the bottle does not always occur. This disadvantage can be explained by the fact that, since the liquors are normally consumed cold, the bottle is usually placed in a refrigerator. Due to the cooling of the liquor and air contained in the bottle, and because of the presence in the closure of the shutter in engagement with its valve seat, a partial vacuum forms in the bottle which is as great as the difference between the temperature of the bottle when it is put into the refrigerator and the temperature within the refrigerator itself.
This partial vacuum prevents or impedes the separation of the valve shutter from the valve seat, resulting in the disadvantage.